The present invention relates to a speaker unit adapted to be embedded in an opening section formed in a mounting part, such as a ceiling or side wall, and also relates to a structure for installing or mounting the speaker unit by embedding it in the opening.
There have heretofore been known embedded-type speaker units (such as ceiling speakers) that are installed or mounted by being embedded in a mounting hole (opening section) formed in a ceiling or the like of a room, as disclosed for example in Japanese Patent Application Laid-open Publication No. 2004-120192 (hereinafter referred to as “the relevant patent literature”). Generally, such a speaker unit includes a cabinet section of a substantially cylindrical shape, and a speaker face provided on the bottom surface of the cabinet section. To mount the speaker unit, the cabinet section is inserted into a mounting hole of the ceiling with the speaker face exposed on the face (i.e., lower surface) of the ceiling, and then the inserted cabinet section is fixed or fastened to the ceiling by fastening via bolts or the like. A mounting structure for such a speaker unit includes a provisionally fastening structure for preventing the heavy speaker unit from falling down by mistake before the fastening via the bolts or the like or after cancellation of the fastening, as disclosed in the relevant patent literature.
The provisionally fastening structure disclosed in the relevant patent literature is constructed in such a manner that, with the cabinet section (speaker housing) inserted in the mounting hole of the ceiling, opposite end portions of a resilient member (provisional fixation member), fixed or fastened to an upper wall of the speaker housing and extending in a reverse side region of the ceiling, abuts against a portion of the reverse side surface of the ceiling adjacent to the outer periphery of the mounting hole. By the abutment, against the reverse side of the ceiling, of the resilient piece, the speaker unit is provisionally fastened in such a manner as to not fall down from the mounting hole.
However, with the provisionally fastening structure disclosed in the relevant patent literature, once the speaker unit is provisionally fastened with the end portions of the resilient piece abutted against the reverse side of the ceiling around the outer periphery of the mounting hole, the abutting engagement of the resilient piece with the ceiling cannot be canceled by only an ordinary operation performed by a speaker-mounting human operator from the face side (lower side) of the ceiling, and thus, the provisionally fastened speaker unit cannot be readily pulled out from the mounting hole of the ceiling. Thus, when the provisionally fastened speaker unit is to be detached for some reason in a speaker unit mounting operation, or when the speaker unit placed in the provisionally fastened position or state after having been released from the fully fixed or fastened state is to be pulled out of the mounting hole of the ceiling in a speaker unit dismounting operation, a disadvantage of poor operability would be encountered.